After the standardization of MPEG-2, a video compression standard (or audio compression standard) has been steadily developed into new standards, such as MPEG-4, H.264/AVC, and High Efficiency Video Coding (HEVC) during the past 10 years. Furthermore, each of the new standards has expanded the utilization area of the MPEG standard while forming a new market, but transport technology, such as the MPEG-2 Transport System (TS), has been widely used in the markets, such as digital broadcasting and mobile broadcasting (e.g., T-DMB and DVB-H), during the past 20 years. The MPEG-2 TS is also widely used in multimedia transport over the Internet, that is, IPTV service, which was not taken into consideration when the standard was established.
However, a current multimedia transport environment is experiencing a significant change from the multimedia transport environment when the MPEG-2 TS was developed. For example, the MPEG-2 TS standard was developed with consideration taken of multimedia data transport over an ATM network when the MPEG-2 TS standard was established, but it is very difficult to fine an example in which the MPEG-2 TS standard has been used for multimedia data transport over the ATM network. Furthermore, the MPEG-2 TS standard has some factors which are inefficient for the recent multimedia transport over the Internet because requirements, including multimedia transport using the Internet, were not taken into consideration when the MPEG-2 TS standard was established. Accordingly, in MPEG, to establish an MPEG Multimedia Transport (MMT) layer, that is, a new multimedia transport standard well-matched with a changing multimedia environment, with consideration taken of multimedia service in the Internet has been recognized as a very important subject.
An important reason why MMT standardization is in progress as described above is that the MPEG-2 TS standard established 20 years ago has not been optimized for the recent IPTV broadcasting service and Internet environment. For this reason, according to an urgent need for a multimedia transport international standard that is optimized for a multimedia transport environment in the recent various heterogeneous networks, in MPEG, MMT standardization is in progress as a new transport technology standard.
When MPEG media is transported, an E-layer and a delivery layer are necessary. The E-layer is classified into four parts; (1) a Media Fragment Unit (MFU), (2) an M-Unit, (3) an MMT Asset, and (4) an MMT package, and the delivery layer is divided into two parts; (1) an MMT Payload Format and (2) an MMT packet. The present invention discloses an MMT overhead structure in which minimized transport overhead has been taken into consideration when transporting media through the MMT layer.